Method of producing detergents



United States Patent Ofiice 3,272,752 Patented Sept. 13, 1966 3,272,752 METHOD OF PRODUCING DETERGENTS Gerhard Hartlapp, Knapsack, near Cologne, and Waldemar Bielenberg, Cologne-Klettenberg, Germany, assignors to Knapsack-Griesheim Aktiengesellschaft, Knapsack, near Cologne, Germany, a corporation of Germany No Drawing. Filed Mar. 6, 1962, Ser. No. 177,759 Claims priority, application Germany, Mar. 7, 1961,

6 Claims. (Cl. 252-135) The present invention relates to a method of producing detergents which consist of a mixture of alkali triphosphate with other components, which in part have detergent properties, and are characterized by the fact that for their production the alkali triphosphate is introduced into an aqueous solution or suspension of all other components or at least a part thereof, and the detergent batch treated in known manner with heat.

Detergents of this type have been known for a long time, but their preparation afforded difficulties insofar as in the case of addition of alkali triphosphate which is free of water to a greater or lesser extent to the detergent batch-also called s1urry--the phosphate withdraws the water from the latter so as thereby to become hydrated in faster or slower manner to Na P O .6H O.

Together with this hydration, the viscosity of the slurry increases which has an extremely detrimental effect on the further processing, as for instance in a spray drying process. 7

It was attempted by increased addition of water to reduce the viscosity of the mixture. This had the disadvantage that in order to evaporate the excess water there was now required a correspondingly large amount of energy which both increased the cost of the process and reduced the capacity of the drying installations.

As long as tripolyphosphate-pyrophosphate mixtures were incorporated in the slurries, the increase in viscosity occurred only to a reduced extent since the pyrophosphate contained in the tripolyphosphate-pyrophosphate mixtures exerted a liquefying .action upon the stirring of a detergent batch (slurry). However, with this method of procedure, a considerable drop in the calcium-combining power must be tolerated, since the calcium-combining power of pyrophosphate is only one-third of the calciumcombining power of sodium tripolyphosphate, and for this reason the use of pure tripolyphosphate is preferred in modern detergents.

It was also endeavored, by using a substantially or completely anhydrous triphosphate to maintain the slurry at a suitable consistency; however, this method also has considerable disadvantages. It is known that anhydrous alkali triphosphate, when stored and transported under normal conditions, absorbs a slight amount of moisture from the air, and passes to a corresponding extent into the hydrated form. This slight water absorption is already suflicient to make the phosphate unsuitable for the known method. It is therefore necessary to heat this salt again to a high temperature shortly before its use up to several hours in order to obtain it in anhydrous form. In this way, this method is made expensive and becomes cumbersome.

It is also known to control the viscosity of the slurries by the introduction of tripolyphosphate mixtures of phase I and of phase II. The preparation of such mixtures having a narrow range of the ratio of phase I to phase II results, however, in increased requirements in connection with the manner of manufacture of the phosphate, and furthermore, the effect of these mixtures is only relatively slight.

Now we have found on basis of extensive investigations, that all of these disadvantages can be eliminated by adding small amounts of calcium compounds to the slurry. A quantity of 0.1 to 2%, and preferably 0.2 to 1% of calcium ions, calculated on the triphosphate employed, is sufficient to influence the viscosity of the detergent in the desired manner.

It is particularly advantageous if the calcium compound is added to the alkali triphosphate, and especially in dry form.

It was very surprising to find that specifically calcium ions produce the observed effect, especially as the alkali triphosphate in a detergent has the mission of eliminating the so-called calcium hardness of the water by combining, in the form of a complex, with the calcium ions present in the water. For this reason, it may appear paradoxical to add Ca-ions from the start to .a substance which combines with calcium. Experiments however, showed that the effective quantity of Ca of 0.1 to 2% of the alkali triphosphate is negligibly small as compared with the amount with which the triphosphate is able to combine.

The calcium-combining power of a good sodium tripolyphosphate is 11.5 grams ca per grams Na P O 100 grams of triphosphate therefore combine with 11.5 grams of Ca. If for instance 0.27% Ca in the form of salts, calculated on the amount of triphosphate, is added to the slurry, the triphosphate loses 2.3% of its original calcium-combining power This slight decrease is not as important as the disadvantages involved in the measures previously carried out to reach the same goal.

Aside from the aforementioned disadvantages of the known methods, when a large excess of water is used, a part of the alkali triphosphate is hydrolyzed during the course of the drying process, and the calcium-combining power of the detergent is thereby considerably impaired.

As calcium compound, Ca(OH) is preferably employed since this product is of low price and can be obtained free of iron; it does not absorb water upon lengthy storage and does not introduce foreign anions. However, other compounds of calcium are also suitable, such as calcium sulfate or any desired mixtures of Ca salts.

The direct measurement of the viscosity of a slurry containing tripolyphos-phate can be carried out by means of a plastograph of the Brabender Company. With this plastograph, the action of a tripolyphosphate on the viscosity of the slurry can be directly measured and recorded as a function of time for a given slurry and constant temperature. The degrees of consistency are measured (1000 degrees of consistency=0.2 mkg.). The moments of rotation produced on the rotatably supported motor housing by the kneading resistance are transferred to a scale and from there to a recorder.

The following examples serve to illustrate the invention but they are not intended to limit it thereto. All percentages are to be understood as percentages by weight.

The examples clearly show that without the addition of calcium to the slurry, the viscosity of the latter, expressed in scale divisions of a plastograph, only a few minutes after the introduction of the triphosphate reaches values which are several times greater than in the case of the addition of calcium.

Magnesium silicate 20 Grams Methyl cellulose 20 Consistency in scale graduations of a plasto- H2O 190 Time in minutes after graph completion of the intro- 110 10H at a temperature of 60 Without addition With 0.2% With 0.5%

of Ca-Com- Ca(OH)z Ca(OH)z Consistency in scale graduations of 21 pounds Time in minutes after plastograph completion of the intro- 30 50 40 duction 070 100 130 Without addition of With 02% Ca (OH); 700 340 150 Cal-compounds 680 450 300 40 as as 030 520 020 740 90 1, 000 90 1,200 150 1,340 250 1,360 350 1, 340 450 Example 5 Example 2 The same slurry was used as in Example 1, at a tem- There was used a detergent of the following compoperature of 80 C. sition:

Consistency in scale graduations of a plastograph Time in minutes after completion of the introduction Without addition With 0.2% With 0.5% With 1% oiCa-compounds Ca(OH)z Ca(OH)i Ca(OH)i Example 3 Grams A slurry of the following composition was used: tnphosphate 400 Grams Tetrapropylene benzene sulfonate 200 Sodium triphosphate 400 Fatty alcohol sulfate 150 Tetrapropylene benzene sulfonate (50%) 400 NaZ.SO4 Nazso 100 Sod1um sil1cat e 50 Sodium silicate 50 Magnesium silicate 20 Magnesium silicate 20 45 g Cellulose %2 Methyl cellulose 20 2 H O 290 at a temperature of 60 C.

at a temperature of 80 C.

Consistenc in scale mduations of last 50 Consistency in scale graduations of a plaste- Time in minutes after y graph 8 p o f 1 5 Fitter graph completion (til the intro Comp 0 g g e mtto' i Without addltlon With 0.2% With 0.5% g gg ggg zgfigg Egg? of Ca-Comanon 0&(011

pounds pounds Example 4 Example 6 There Was used a slurry of the following p si 65 There was used a slurry of the following composition:

rams Sodium triphosphate 400 Grams Tetrapropylene benzene sulfonate (50%) 200 Sodlum trlpolyphosphate 400 Fatty alcohol ulfat 5% Tetrapropylene benzene sulfonate (50%) 300 10 50 100 Fatty alcohol sulfate (65 1S6 Sodium silicate 5O 70 a i 100 Magnesium silicate 20 sodlumlllcaffif 50 Methyl cellulose 20 Magnesium silicate 20 0 3 Methyl cellulose 20 at a temperature of 80 C.

at a temperature of 60 C.

The above slurry was examined with an addition of water of 284 grams, 384 grams and 484 grams and compared with an identical slurry containing 284 grams of H 0 and different additions of Ca-salt.

with merely a part of the detergent composition components, and thereafter the resulting mixture is mixed with the remaining components of the detergent composition.

4. The method of claim 1 wherein the calcium salt Consistency in scale graduations of a plastograph Time in minutes after Slurry-F284 g. 11 0 completion of the introduction Slurry 1 Slurry 1 Slurry 1 +284 g. +384 g. +484 g.

H 0 H 0 H With With With 0.1% 0.25% 0.5% Ca(0H)z Ca(OH) Ca(OH)2 1 Without addition of Oa-salt.

It is clear from this that a slurry containing 284 g. H O+0.5% Ca(OH) corresponds in viscosity to a slurry containing 484 g. H O. In this case, 13% water could be saved.

We claim:

11. In the method of producing detergent compositions consisting essentially of alkali metal triphosphates selected from the group consisting of sodium tripolyphosphate and potassium tripolyphosphates, and other conventional detergent components from an aqueous slurry containing the alkali metal triphosphates and at least a part of said other detergent components, the improvement which comprises adding to the slurry 0.1 to 2.0% by weight of a calcium salt which ionizes substantially complete in the slurry, the amount of the calcium salt being calculated on the amount of alkali metal triphosphate present in the slurry, and spray-drying the resulting mixture.

2. The method of claim 1 wherein the calcium salt is added to the slurry in an amount of 0.2 to 1% by weight, calculated on the amount of alkali metal tripolyphosphate present in the slurry.

3. The method of claim 1 wherein the alkali metal tripolyphosphate and the calcium salt are mixed initially is selected from the group consisting of Ca(OH) and 03.80421'120.

5. The method of claim 1 wherein the calcium salt is added to the slurry in admixture with the alkali metal tripolyphosphate.

6. The method of claim 4 wherein calcium salt is admixed while dry with the alkali metal tripolyphosphate.

LEON D. ROSDOL, Primary Examiner.

JULIUS GREENWALD, Examiner.

J. WELSH, J. T. FEDIGAN, Assistant Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3,2 2,752 September 13, 1966 Gerhard Hartlapp et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Calumn 4, 1n the first table, fourth column, line 7 thereof, 101 "620" read 5Z0 column 6, line 38, for Knapsacik et all)" read Rodls et a1.

Slgned and sealed this 26th day of September 1967.

(SEAL) Attest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents 

1. IN THE METHOD OF PRODUCING DETERGENT COMPOSITIONS CONSISTING ESSENTIALLY OF ALKALI METAL TRIPHOSPHATES SELECTED FROM THE GROUP CONSISTING OF SODIUM TRIPOLYPHOSPHATE AND POTASSIUM TRIPOLYPHOSPHATES, AND OTHER CONVENTIONAL DETERGENT COMPONENTS FROM AN AQUEOUS SLURRY CONTAINING THE ALKALI METAL TRIPHOSPHATES AND AT LEAST A PART OF SAID OTHER DETERGENT COMPONENTS, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE SLURRY 0.1 TO 2.0% BY WEIGHT OF A CALCIUM SALT WHICH IONIZES SUBSTANTIALLY COMPLETE IN THE SLURRY, THE AMOUNT OF THE CALCIUM SALT BEING CALCULATED ON THE AMOUNT OF ALKALI METAL TRIPHOSPHATE PRESENT IN THE SLURRY, AND SPRAY-DRYING THE RESULTING MIXTURE. 